Acne is a common and complex skin disease with an extremely complex pathogenesis. Although an association between acne and insulin resistance has been established in women, particularly in women with polycystic ovary syndrome, the association has not been studied in men. Recently, Italian physician FabbrociniG conducted a randomized clinical trial evaluating the efficacy of metformin and dietary modification in men with treatment-resistant acne, the results of which were published in ClinExpDermatol. The study suggests that diet and insulin resistance play an important role in acne pathogenesis, and that young male acne patients who are resistant to common treatments may have metabolic abnormalities and reduced insulin sensitivity, and that metformin administration in these patients may reduce GAGS scores and insulin resistance. Insulin-like growth factor (IGF-1) is known to stimulate androgen production in the gonads and adrenals, which stimulates follicular sebaceous gland cell growth, and is also involved in the production of acne by androgens, growth factors, and glucocorticoids.